This invention relates to methods and apparatuses for locking and unlocking doors, such as for example, van doors equipped with safety rod locks.
In one class of safety rod lock for vans, each door has an upper keeper mounted to the van frame above the door and has a lower keeper mounted to the van frame below the door along a vertical line with the upper keeper. The upper and lower keepers are adapted to mate with the vertical rods, which serve as lock bolts. There is an outside lock portion for moving the rods and keepers with respect to each other. The lock bolt or rod is positioned against the outside surface of the door near its edge to hold the door from opening when the ends of the bolt are held by the keepers. A lever moves the rod to free it from or to engage it with the keepers.
In a prior art type of lock in this class, the lever is fastened by a padlock on the outside of the van to be locked and unlocked by a key. In another prior art type of lock in this class, the cam rods are held together by two steel matching loops locked by a padlock in their center. In all of these cases the lock is accessible from outside the van and can be removed.
This type of prior art lock has a disadvantage in that the lock itself is readily available to persons who wish to remove it. Even padlocks that have protective shielding such as metal can be reached and opened.